The present invention relates to collection of blood for use in blood transfusions.
In the collection of blood, when the needle is inserted into the skin, and particularly when the needle is moved around to find the vein, there is generally some tissue trauma. Normally the tissue trauma that results from cutting or opening the skin causes the release of an amount of tissue thromboplastin to aid in the proper clotting of the blood.
However, it has been found that blood collected for use in blood transfusions should be free of tissue thromboplastin, even in low levels, because any tissue thromboplastin that is present will cause activation of the fibrinolytic system. Such activation can in turn result in decreased levels of antihemophilic factor (AHF) and platelets. AHF and platelets are components prepared from fresh blood and find uses in the treatment of hemophilia A and cancer, respectively. These disease conditions require treatment with relatively large amounts of the respective blood components.
It is, therefore, an object of the present invention to provide a device and method for reducing tissue thromboplastin in collected blood.
Another object of the present invention is to provide an efficient device for removing the initial volume of blood collected, which initial volume is expected to have the greatest possibility of tissue fluid contamination.
Another object of the present invention is to provide a system that is simple in construction and easy to use which aids in maximizing the levels of available AHF and platelets in collected blood, by preventing an initial volume of collected blood from entering the main blood container.
Other objects and advantages of the invention will become apparent as the description proceeds.